Cortical learning via sensorimotor experiences evoked by bodily movements begins as early as the foetal period. However, the learning mechanisms by which sensorimotor experiences guide cortical learning remain unknown owing to technical and ethical difficulties. To bridge this gap, we present an embodied brain model of a human foetus as a coupled brain-body-environment system by integrating anatomical/physiological data. Using this model, we show how intrauterine sensorimotor experiences related to bodily movements induce specific statistical regularities in somatosensory feedback that facilitate cortical learning of body representations and subsequent visual-somatosensory integration. We also show how extrauterine sensorimotor experiences affect these processes. Our embodied brain model can provide a novel computational approach to the mechanistic understanding of cortical learning based on sensorimotor experiences mediated by complex interactions between the body, environment and nervous system.

Background: Since diazoxide was approved for clinical use in Japan in 2008, its prescription for the treatment of infants with hyperinsulinemic hypoglycemia (HIH) has rapidly expanded. Concomitantly, reports of complications associated with diazoxide are increasing. Objectives: To clarify the trends and problems associated with the treatment of infants with HIH, we planned a nationwide surveillance in Japan. Methods: Questionnaires were sent to 255 institutions belonging to the Japanese Neonatologist Association inquiring about neonatal cases of HIH from 2009 to 2011. Results: One hundred nineteen cases of neonates with transient HIH (THIH) related to perinatal problems and 15 cases with permanent HIH (PHIH; hypoglycemia persisting beyond a year) or genetic HIH were reported. Sixty-four infants (53.8%) with THIH were administered diazoxide, and the administration was completed within 3 months in 46 infants (71.9%). Fourteen of the PHIH or genetic cases were treated with diazoxide and 7 of them (50%) had hypoglycemia persisting beyond a year. Circulatory complications were reported in 15 infants, i.e. 10 with THIH and 5 with PHIH. Multiple regression analysis revealed that a younger gestational age at birth and higher maximum doses of diazoxide were significant risk factors for circulatory complications. Conclusions: Diazoxide is widely prescribed for infants with HIH as a first-line medicine in Japan, but prophylactic diuretics are uncommon. Under these circumstances, a high prevalence of severe circulatory complications in very-low-birth-weight infants was reported.

VLBW infants showed a characteristic pattern in the HPA axis at 2 weeks of age: higher basal cortisol values and lower response to CRH tests. This study suggested that AG was related to the lower response to CRH tests, at least partly.

Anatomical studies show the existence of corticomotor neuronal projections to the spinal cord before birth, but whether the primary motor cortex drives muscle activity in neonatal 'spontaneous' movements is unclear. To investigate this issue, we calculated corticomuscular coherence (CMC) and Granger causality in human neonates. CMC is widely used as an index of functional connectivity between the primary motor cortex and limb muscles, and Granger causality is used across many fields of science to detect the direction of coherence. To calculate CMC and Granger causality, we used electroencephalography (EEG) to measure activity over the cortical region that governs leg muscles, and surface electromyography (EMG) over the right and left tibialis anterior muscles, in 15 healthy term and preterm neonates, during spontaneous movements without any external stimulation. We found that 17 leg muscles (10 right, seven left) in 12 neonates showed significant CMC, whose magnitude significantly correlated with postnatal age only in the beta frequency band. Further analysis revealed Granger causal drive from EEG to EMG in 14 leg muscles. Our findings suggest that the primary motor cortex drives muscle activity when neonates move their limbs. Moreover, the positive correlation between CMC magnitude and postnatal age suggests that corticomuscular communication begins to develop during the neonatal stage. This process may facilitate sensory-motor integration and activity-dependent development.